Literal translation: Manifestation art (obviously fullbring is better, right?). It is an art of maximising the capacity of an object you hold dear by pulling out its 'soul' and resonating it with yours. It could be anything as every object has a 'soul'. Hence the object with which you're most functional is called your FullBring

Girl: (exhausted) That was great, Melissa! How did you do that?
Melissa: I thought I told you, this strap-on is my fullbring.